Fire arch for furnaces



May 7,. 1929. L. s. ABBOTT FIRE ARCH FOR FURNACES Filed April 4, 1937 Patented May 7, 1929.

LYLE STOCKTON ABBOTT, OF CHICAGO, ILLINOIS.

FIRE Anon non runnnons.

Application filed April 4,

, My invention relates to fire arches for furnaces particularly the character wherein a plurality of refractory tile or firebricks are supported by arch bars in such. a manner as to form an arch having the lower portion thereof Where it is exposed to the direct heat within the furnace composed entirely of fire brick and in which the supporting means for the fire brick is protected by the brick themselves. v

It is a purpose of this invention to provide an arch of this character which shall be composed of very few parts and'yet which will retain the desired amount of flexibility to enable it to expand and contract and adjust itself to the changes in temperature undergone in use with the furnace. It is another object of this invention to provide an arch of this character with novel means for permitting the refractory elements and the supporting bars to adjust themselves relative to each other in order to take care of the difference in expansion and contraction between the supporting bars and the refractory material without subjecting either of them to any undue strain because of this difference.

In constructing fire arches for furnaces it 7 is always necessary that the supporting beams and hanger bars for the, tile be protected from the direct heat of the furnace and this makes it necessary to provide tile of such a character that they will close the space beneath the hanger bars and the supporting beams. But, it is also necessary in an arch of this character. to provide means for taking care of the expansion andcontraction of therefractory tile and of the supporting means so that the expansion of the various elements that make up the arch will not cause it to bind andsubject any of the refractory tile'to a very great pressure since such a pressure would result in the destruction of the tile which have very little resistance to compressive pressure. It is neces-' sa ry therefore to so support thejtileumembers within the arch that they may expand in any direction'within limitsand in this Way adjust themselves to the various temper'atures of the furnace. a

It is a purpose of this invention to provide supporting means for the tile members which will permit the adjustment. without in any way detracting from the strength of the arch from a mechanical standpoint and without leaving openings between the'refractory ele- 1927. Serial no. 180,913.

ments through which the heat might attack the supporting means.

Other objects and advantages of the invention will appear as the description proceeds when taken in connection with the accompanying drawing. However, I with it .to be distinctly understood that I do not intend to limit myself to the exact details shown and described; but that I intend to avail myself of all modifications as would occur to one skilled in this art and asfall withinthe'scope of the claims.

In the drawings:

Fig. 1 is a plan vlew of a portion of a furnace arch constructed in accordance with my invention Fig. 2 is a side view of the portion of the arch shown in Fig. 1;

Fig. 3 is a side View of the arch taken at right angles to Fig. 2;

Fig. 4c-is a perspectlve view of one ofthe I refractory tile members used in the arch; and

' Fig. 5 is a perspective view ofthe other refractory tile member used.

Referring now in detail to the drawings,

the archis supported by means of a plurality of beams 10 and 11 whichextend acrossthe furnace and are secured in any suitable manner to the side walls 12 thereof. These supporting members are each made up of a plurality of channel bars 13 and 14 having the flanges thereof facing each other and i being spaced apart by means of the spacing.

with the horizontal extending bars 19 and i 20 resting upon the lower flanges of the channel beams and these bars 19 and 20 are rounded on their lower surface as shown at 21 in Fig. 3 to permit. a 'slightrocking movement of the supporting members 17 relative to the flanges of the channel beams for a purpose which, will presently appear. The supporting elements 17 as shown clearly in Fig. 3 are forked at their lower ends to receive the arch bars 18 which are provided adjacent their upper edges with the en'- larged portions 24 over which the legs 22 and 23 of the membersl? fitand pivoted thereto by means of the bolts'25.

The arch bars which are preferably cast in one piece are enlarged at their upper and lower edges to reenforce the same and are provided at spaced intervals throughout their length with integral projections 26 and 27 extending from opposite sides thereof slightly above the enlarged door reenforcing edge. These projections 26 and 27 are substantially semi-cylindrical in cross section to provide a rounded upper surfaceupon which the refractory tile members 28 having the oval openings 29 therethrough may be supported. Refractory members 28 as shown clearly in Fig. '5 are recessed on opposite sides adjacent the top end thereof as at 31 and 82 and the opening 29 extendstransversely through the thinner upper portion provided by the recesses 31 and 32. This opening as hereinbefore stated is oval in shape being elongated longitudinally horizontally of the block to provide for limited movementrelative to the bars 26 and 27 in order to permit for adjustment of these blocks upon expansion of the arch relative to the arch. bars 18. This is made necessary because of the, fact that-the expansion per unit length for a definite change in temperature is' not the same for the cast bar 18 as it is for the refractory tile membersf As shown by F 3 each one of the bars 18-carries a row of the tile members 28 on each side .thereof by means of the horizontal projections 26 and 27, the recessed portions 31 and 32 permitting the members 28 to come together beneath. the bars 18 so as to cut them off from any direct attack of the hot gaseswithinthe furnace. The outside recess faces of the members 28 form seats for the projections 34 and 35 on the blocks '33 sons to support them between the rows of'refractory members28 carried by the bars 18 and thus form a complete closed arch for. the furnace. Thus bycsuspending the requisite number of the bars 18 from the channel members and in turn supporting the refractory tile28 from the bars 18 and filling in the spaces between the tile 28 with the tile v38, the furnace arch may be built up across the chamber. 1

Side walls of the furnace are preferably provided with a shoulder 36 over which the end tile members 28 will project and any suitable resilient packing 37, such as asbestos or mineral wool, may be provided to close the space between the side walls and the arch and permit expansion and contraction atthis point. i

By the provision of the rounded lower faces on the T shaped member made of the suspension members 17, these members may adjust themselves slightly with respect to the-channel beams when the refractory tile members are expanded longitudinally of the channel beams under increase of the jtemperaturein the furnace and since the the changes in temperature encountered in tively cool, whichprevents deterioration-"of heads of the members 17 are free to slide longitudinally of the channel beams, they will readily adjust themselves so as to prevent any undue strain on the tile due to this expansion. The expansion longitudi- 7O nally of the arch bars 18 is also taken care of by means of the elongated holes in the refractory tile supported on members 26 and 27 which permit the tile 28 to have a slight movement longitudinally of the bars 18 to take care of the difference in the expansion between the'metallic bars and-the refractory tile.

From the foregoing description it will be 5 seen that it have provided "furnace arch which is constructed of. arelativc-ly few simple parts easily assembled or disassembled. for the purpose of replacement and which is capable of adjusting itself-under'-' the surface in a furnace and the danger of breaking the refractory tile. Also, the tile members which are used in this structure are so constructed that there are no sharp projecting portions which are liable to be broken off in handling-or making the tile since there are no reentrant angles to cause difficult-yin molding the tile and firing them.

Furthermore,'by the provision of the particular type of arch bar and the meansfor supporting the tile thereon, the bars in the upper portions of the refractory tile are exposed so that the air may have ready access. thereto and maintain them compara-l the arch bar and also lessens the liability. of any breakage in the structure."

From the above description; it. is'thought the construction andadvantages of my device will be clearly apparent to those skilled in this art. 7

Having thus described my invention, what I desire to claim and secure by United States Letters Patent is: I

v 1. In a furnace arch, the combination of an arch. bar having a row of longitudinally spaced horizontally extending projections .on each sidethereof, each of said rows of 1 projections'supporting a'row of refractory tile thereon, the tile in said rows havinginwardly offset portions extending from the top thereof below the lower edge of said bar, and having openings therethrough receiving, said projections, the adjacent faces of said rows of tile being in Contact below said bar. 3 V

2. In a furnace arch the combination of an arch bar having a row of longitudinally spaced horizontally. extending projections on each side thereof, each of sald rows of projections supportinga row ofrefractory tile thereon, the tile in said rows having openings therethrough receiving said projections, said openingsbeing larger horizontally in a'direction'lengthwise of said bar than said projections to permit limited longitudinal adjustment of said tile on said bar.

3. In a furnace arch the combination of an arch bar having a row of longitudinally spaced horizontally extending projections on each side thereof, each of said rows of projections supporting a row of refractory tile thereon, the tile in said rows having openings therethrough receiving said projections, said projections having rounded upper surfaces engaging the tile.

4. In a furnace arch, the combination of a plurality of spaced parallel arch bars each having a row of longitudinally spaced horizontally extending projections on each side thereof, each of said rows of projections supporting a row of refractory tile thereon, the tile in said rows having inwardly offset portions extending from the top thereof below the lower edge of said bar, the adjacent faces of said rows of tile being in contact below said bar, and rows of refractory tile between adjacent bars having projections resting upon the shoulders formed by the offsets in the outer faces of the tile carried by said bars.

zontal projections on opposite sides of each of said bars, a row of refractory tile supported by each row of projections the tile in said rows having a shoulder formed thereon adjacent 'thetop thereof, and rows of refractory tile between the rows of tile carried by said projections having projections resting on said shoulders.

6. A. furnace arch construction comprising a plurality of arch bars, means for supporting said arch bars in spaced relation, each of said bars having integral therewith longitudinally spaced horizontal projections on opposite sides thereof, a tile carried by each of said projections and a plurality of tile connected and supported by the tile on the projections'of adjacent arch bars.

In witness whereof, I hereunto subscribe by 7name this 29th day of March, A. D., 192

LYLE STOCKTON ABBOTT. 

